What I wrote doesn't match what Chad Waterbury wants you to do in the workout. You are supposed to do all the set of A1 with 60s rest before moving on to A2, etc.
Now, as for the weight, CW is really good about his weight limits. Try the program. If you picked the correct weight, it is going to be a struggle and you are going to grow. Of course, you need to be eating correctly, working out correctly and, importantly, resting correctly.
Read through the article discussion to make sure you understand some of your options and get some further insight.